A Fire's Carbon Footprint

-Jody Lee, Producer, Outdoor Idaho

Looking into the science of climate change as it affects wild fires leads to the discovery of a feedback loop – what if wild fires contribute to climate change, which then creates a ripe breeding ground for more wild fires? Are we dealing with a vicious cycle of warmer weather leading to intense wild fires, which then create warmer weather which then promotes wild fires? Could be.

First of all, a carbon footprint, according to www.carbonfootprint.com is "a measure of the impact our activities have on the environment, and in particular climate change. It relates to the amount of greenhouse gases produced in our day-to-day lives through burning fossil fuels for electricity, heating and transportation etc." Simply put, our emissions of CO2 (carbon dioxide), usually measured in units of tons or kilograms, constitute our carbon footprint. What then, is the impact of mega-fires on the climate, as they release all that stored carbon into the atmosphere? What is the affect of that footprint?

Studies confirm that hotter temperatures remain the primary contributing factor in wild fire risk (see PNW Science Update article: “Western Forests, Fire Risk, and Climate Change”), compared to other factors such as insects, disease and drought. A recent study by two Colorado researchers (Jason Neff, University of Colorado at Boulder and Christine Wiedinmyer at the National Center for Atmospheric Research) measured greenhouse gases pumped into the atmosphere by these fires, and concluded that U.S. wild fires create more carbon dioxide emissions in a year than the state of Pennsylvania does. “On average, wildfires in the United States each year pump 322 million tons of carbon dioxide. That’s about 5% of what the country emits by burning fossil fuels, such as gasoline and coal.” (AP/MSNBC article on study November 1, 2007) The study confirms that our fossil fuel use far outweighs wild fires in emissions, but the additional carbon, especially in the wild fire month of August, does not help our pollution/air quality and long-term climate change issues.

Scientists studying the effect of these fire emissions reaching the stratosphere arrived at further complications. “The chemical junk that forest fires spew into the air might affect atmospheric chemistry in a manner similar to – and on a scale similar to – the impact of sulfurous chemicals from volcanic eruptions.” (“Forest fires burn their way into climate change,” Christian Science Monitor, Robert C. Cowen – see below.) This research investigates the “copycat” relationship between wild fires and volcanoes – both release chemicals into the stratosphere, which can spread around the world, impacting cloud formation, weather and climate change.

With this feedback loop – climate change affecting wild fires, wild fires affecting climate change, the issues faced by those who manage our public lands become much more complicated. Wildland Fire Use fires still release tons of carbon into the atmosphere, impacting our climate; controlled burns also release carbon. Harvesting and thinning removes the trees storing the carbon. Aggressive fire suppression? We’ve tried that. What to do. And then there’s politics.

"In early 2007, the United Nations panel of climate scientists reported that the amount of carbon dioxide in the atmosphere is increasing faster than ever before. Unless greenhouse emissions are cut aggressively, the report says, ´temperatures could increase by 5 degrees Fahrenheit by century's end – enough to create a planet much warmer than humans have ever known.´"— FRONTLINE "Hot Politics" February 2007 (watch the entire program)